Last week, the European Union issued a statement on the Joint Comprehensive Plan of Action, the nuclear weapons deal concluded with Iran’s rulers, from which President Trump withdrew three months ago.

“The JCPOA is working and delivering on its goal, namely to ensure that the Iranian programme remains exclusively peaceful as confirmed by the International Atomic Energy Agency (IAEA) in 11 consecutive reports,” the statement asserted. “It is a key element of the global nuclear non-proliferation architecture, crucial for the security of Europe, the region, and the entire world. We expect Iran to continue to fully implement all of its nuclear commitments under the JCPOA.”

One problem: The statement is “wholly misleading.” That’s the analysis of Olli Heinonen, who served at the IAEA for 27 years, including as its deputy director general and as head of its Department of Safeguards.

He is currently senior advisor on Science and Nonproliferation at the Foundation for Defense if Democracies (where I hang my hat) and a senior fellow at Harvard University’s Belfer Center for Science and International Affairs.

Mr. Heinonen explained that the IAEA simply has not said what the EU claims it has said: “The IAEA has only said in its reports that it has continued to verify non-diversion of declared nuclear material, but it has not confirmed that Iran’s nuclear program remains exclusively peaceful.”

Such a conclusion “can only be given by the IAEA — according to its procedures and practices when it has completed evaluations regarding the absence of undeclared nuclear material and activities, which it has not yet done. According to the latest IAEA report on 24 May 2018, that evaluation work is still ongoing.”

Mr. Heinonen noted, too, that Iran has not been dismantling its nuclear program, but instead “proceeds with the development of new centrifuges, piles up uranium (yellow cake), and is quietly building infrastructure.”

He added that the nuclear archive recently smuggled out of Tehran by Israel’s Mossad “casts a long shadow of doubt over Iran’s intentions.” The EU seems determined to disregard this intelligence.

More broadly, our friends across the pond insist upon viewing Iran’s theocrats through rose-colored glasses — whitewashing or ignoring their malevolent and illicit activities.

By now, no one should need to be reminded that those activities include: Funding and instructing jihadist terrorists in multiple countries, enabling Bashar Assad’s mass murders in Syria, illicitly arming Houthi rebels in Yemen, backing al Qaeda-linked groups in Afghanistan, developing missiles that can carry nuclear warheads, threatening access to international waterways, and egregiously violating fundamental human rights at home — most recently imprisoning Iranian Christians on the curious charge of “orientation toward the land of Christianity.”

Even crimes committed on European soil have failed to make an impact. In late June, Belgian, French and German security authorities foiled a plot to bomb a large gathering in Paris of Iranian dissidents in exile, a meeting prominent Europeans and Americans also were attending.

The alleged mastermind behind this attempted terrorist attack: Assadollah Assadi, an Iranian diplomat based in Vienna. Arrested in Germany, where he enjoys no diplomatic immunity, he reportedly recruited Belgian citizens of Iranian descent and provided them with explosives during a meeting in Luxembourg.

A few weeks later, the Dutch expelled two Iranian diplomats linked to the assassination of Ahmad Mola Nissi, an Iranian dissident.

Drops in a large and lethal bucket: Agents of the Islamic Republic have been committing murders and terrorist acts in Europe for decades, as a report issued in July by the U.S. National Counterterrorism Center makes clear. “Select Iran-Sponsored Operational Activity in Europe, 1979-2018” notes: “Iran’s regime has brought suffering and death to the world and its own people. Just in Europe, Iran-sponsored assassinations, bombings, and other terrorist attacks have scarred countless lives.”

Yet EU foreign affairs chief Federica Mogherini was all smiles and bonhomie when she met with Iranian Foreign Minister Javad Zarif in Vienna last month. In an interview with The Wall Street Journal, an unnamed French official offered one reason why Europeans don’t hold Iran’s rulers to account. Asked about the attempted bombing in Paris, he said: “We can imagine an ultranationalist faction carrying out an operation to raise tensions.”

I’m reminded of an old song: “Imagination is crazy/Your whole perspective gets hazy/Starts you asking a daisy/What to do, what to do?”

Maybe it was a daisy that told the EU to attempt to relieve the sanctions pressure the Trump administration has begun to reimpose on Iran’s ruling mullahs. Officially, the EU actually “forbids EU persons from complying with those sanctions, unless exceptionally authorized to do so.”

These efforts have so far been unavailing. Few European corporations are willing to risk being barred from the American market.

In fairness, a European colleague has suggested a charitable explanation for the behavior of EU officials: They’re playing good cop to Mr. Trump’s bad cop. They are maintaining a diplomatic dialogue with the clerical regime and, perhaps, causing it to exercise some restraint and delay some aspects of its nuclear weapons program.

Are you convinced? Neither am I. More plausible, I think, is that German, French and British leaders have formulated policies based on their visceral dislike of President Trump, their reluctance to admit they acquiesced to President Obama’s JCPOA despite being smart enough to recognize its fatal flaws, and their faith — undiminished by time and experience — in the efficacy of appeasement.

• Clifford D. May is president of the Foundation for Defense of Democracies (FDD) and a columnist for The Washington Times.